Thermal and acoustic insulation properties in nanoporous geopolymer nanocomposite

In building and construction sector, seeking for high thermal and sound insulation materials is crucial to reach lower carbon footprints and also for curtailed consumption energy either for heating or for cooling. Nowadays, geopolymer nanocomposites, an alternative binder to Ordinary Portland Cement (OPC), are drawing considerable attention for their great prospective to withstand heat and sound exposure beside to their outstanding properties including high early strength, little creep and shrinkage and a good resistance to corrosion and abrasion. To advance geopolymer insulating properties, a nanoscale analysis has been investigated here to consider porosity, nanopore size, moisture as well as chemical composition and alkali agents impacts. Our findings conclude that a better thermal isolation is predicted for a high-silicon content geopolymer nanostructure with the presence of sodium alkali activators. The lowest thermal conductivity values of 0.08 W/m.K and 0.10 W/m.K are obtained for a porosity of 30.8% for Na+ and K+ samples, respectively. Considering humidity, results indicate that residual water enhances 4.5 times the thermal insulation of a highly nanoporous metakaolin geopolymer rich on silicon and in the presence of NaOH alkali activator. Nanoscale investigation has finally shown a promising acoustic insulation behavior than OPC material when pore size and porosity are higher than 12 angstrom and 20% respectively, making nano -porous geopolymer paste as a great challenge for cementitious materials.

Automated summary

In the construction industry, the search for high thermal and sound insulation materials is crucial for reducing carbon footprints and energy consumption. Geopolymer nanocomposites are gaining attention as an alternative binder to Ordinary Portland Cement (OPC) due to their excellent properties including high strength, resistance to corrosion and abrasion, and ability to withstand heat and sound exposure. This study investigates the nanoscale analysis of geopolymer materials to enhance their insulation properties, considering factors such as porosity, nanopore size, moisture, and chemical composition. The findings suggest that geopolymer with a high-silicon content and sodium alkali activators exhibits better thermal isolation. Additionally, the presence of residual water significantly enhances the thermal insulation of highly nanoporous metakaolin geopolymer. Lastly, the nanoscale investigation shows that nano-porous geopolymer paste with pore size and porosity higher than 12 angstrom and 20% respectively has promising acoustic insulation properties, making it a great challenge for cementitious materials.